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Difference between JSON.stringify and JSON.parse
...pt object into JSON text and stores that JSON text in a string, eg:
var my_object = { key_1: "some text", key_2: true, key_3: 5 };
var object_as_string = JSON.stringify(my_object);
// "{"key_1":"some text","key_2":true,"key_3":5}"
typeof(object_as_string);
// "string"
JSON.parse turns a...
Why can templates only be implemented in the header file?
...f;
When reading this line, the compiler will create a new class (let's call it FooInt), which is equivalent to the following:
struct FooInt
{
int bar;
void doSomething(int param) {/* do stuff using int */}
}
Consequently, the compiler needs to have access to the implementation of the m...
How ViewBag in ASP.NET MVC works
... properties such as ViewBag.Foo and magic strings ViewBag["Hello"] actually work?
7 Answers
...
what is the difference between 'transform' and 'fit_transform' in sklearn
...is meant for when you have already computed PCA, i.e. if you have already called its .fit method.
In [12]: pc2 = RandomizedPCA(n_components=3)
In [13]: pc2.transform(X) # can't transform because it does not know how to do it.
-------------------------------------------------------------------------...
Temporarily disable auto_now / auto_now_add
...s:
# my model
class FooBar(models.Model):
title = models.CharField(max_length=255)
updated_at = models.DateTimeField(auto_now=True, auto_now_add=True)
# my tests
foo = FooBar.objects.get(pk=1)
# force a timestamp
lastweek = datetime.datetime.now() - datetime.timedelta(days=7)
FooBar.obj...
AtomicInteger lazySet vs. set
...l values for a while, but you'd
like to ensure that structures are eventually GCable. In such
cases, you can get better performance by avoiding
the costs of the null volatile-write. There are a few
other use cases along these lines for non-reference-based
atomics as well, so the method is ...
SyntaxError: Non-ASCII character '\xa3' in file when function returns '£'
... First line is to make the py file executable on *nix. It is not really related to this question.
– cmd
Dec 15 '17 at 20:21
...
Why does Javascript's regex.exec() not always return the same value? [duplicate]
... matches by performing the assignment as the loop condition.
var re = /foo_(\d+)/g,
str = "text foo_123 more text foo_456 foo_789 end text",
match,
results = [];
while (match = re.exec(str))
results.push(+match[1]);
DEMO: http://jsfiddle.net/pPW8Y/
If you don't like the placem...
Difference between “module.exports” and “exports” in the CommonJs Module System
...ns to be set to module.exports.
At the end of your file, node.js will basically 'return' module.exports to the require function. A simplified way to view a JS file in Node could be this:
var module = { exports: {} };
var exports = module.exports;
// your code
return module.exports;
If you set a...
How do I install Python OpenCV through Conda?
I'm trying to install OpenCV for Python through Anaconda , but I can't seem to figure this out.
41 Answers
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